78 f-250

Symptoms that all started yesterday:

• Will not crank over at all
• Starter Solenoid buzzes
• horn "briefly" honked by itself a couple times
• Stereo comes on then right back off (key in run & in accy position)

Things I've replaced today

• Starter was bad - replaced
• New Starter Solenoid

Things I've replaced in the past that are electrical:

• One wire alternator - 170A from JBG
• Mark VIII fan - bought wiring kit w/tem switches (works great)

I am only getting 3-5 volts at the "S" terminal on the starter solenoid while cranking. Battery is at 12v. All the connections look good.

What is causing this problem?

Is it the ignition/key switch?

I'm at my witts end with this! Good advice is greatly appreciated!!

 

How are the battery cables, they can look good from the outside but typically corrode from the inside out.

 

Cables are all new. Forgot to mention that I replaced them too.

 

Have you tried jumping the solenoid?

 

yes. For whatever reason jumping the solenoid just makes it buzz same result as turning the key to crank position.

I'm jumping it from the battery post to the "S" post. Is this correct?

 

That's correct, have you tried jumping across the two large lugs to rule out a faulty solenoid? (even though it's new).

 

Nothing happens except slight sparking when I jump it from each big post.

 

It should crank your starter over, you're using a length of battery cable to jump it correct?

 

I used channel lock pliers to jump it.

I just removed the ignition switch, cleaned the connections and tried to crank it again with the switch just hanging under the dash & saw a little bit of smoke come out of it....

 

Most likely it's a faulty ignition switch since you've ruled out the solenoid.

 

New battery cables, ignition switch, starter & two solenoids... Still have the same issues...

Battery had 11.8 volts, charged back up nicely to 12.6... Battery is less than 1 year old.

Figured it had to be the battery since that was all that was left... Swapped in the battery from my work truck for a test & she fired right up!!!

The thing that had me thinking it wasn't the battery is because I tried HD jumper cables off of my diesel and nothing changed.

I've seen batteries do some strange things before in my bassboat, but this is a new one on me. I thought the battery might be the problem after the solenoid didn't fix the problem & since jumping the posts on the solenoid wouldn't crank her over.

Stupid battery shows over 12 volts & still doesn't have enough "UMPH" to turn over a starter motor.

Lesson learned... battery voltage is NOT an indicator of true battery condition.

I hope that this post will save someone a lot of trouble. i.e. - if you have these symptoms... try swapping in another battery from a running vehicle before spending any money on new parts.

I'm not too concerned about 'ol Blue having all these new parts since I'll have my new TMI 400 in a few more weeks & the ZF-5 to go with it...

 

12 volts doesn't mean she has enough amps to crank over. I run a battery for a 2005 f250 with the V-10. It
Just barely fits the stock tray. Alot more cranking amps and reserve. Goes along great with a 3G alternator.

 

Amps turn the starter, not voltage, although voltage is the easiest to check. I buy the biggest Interstate battery I can get for my dent-sides. I think they're 850 cca (can't remember for sure). They cost a little more, but I very rarely have trouble starting one.

 

I wasn't thinking battery either, usually 12v is enough for the battery to at least make a feeble attempt to turn the motor over.

 

A buzzing solenoid in my experience almost always means not enough juice in battery to crank motor.